Update the link to the mailing list in the README
Update the link to the mailing list in the README

duncanmortimer/ledger,paulbdavis/ledger,duncanmortimer/ledger,duncanmortimer/ledger,jwakely/ledger,ledger/ledger,paulbdavis/ledger,ledger/ledger,paulbdavis/ledger,jwakely/ledger,paulbdavis/ledger,afh/ledger,afh/ledger,duncanmortimer/ledger,jwakely/ledger,duncanmortimer/ledger,jwakely/ledger,jwakely/ledger,paulbdavis/ledger,afh/ledger,duncanmortimer/ledger,ledger/ledger,afh/ledger,ledger/ledger,jwakely/ledger,paulbdavis/ledger,paulbdavis/ledger,afh/ledger,ledger/ledger,jwakely/ledger,duncanmortimer/ledger